Polyurethane or polyisocyanurate foams are used in many applications today. Because of their widespread use, much research has been done on providing flame retardancy to polyurethane or polyisocyanurate foams. To this end, halogenated flame retardants and phosphorus flame retardants have been used to provide these flame retardant properties. For example, alkylated aryl phosphates are known in the art to be useful as flame-retardants in such applications. However, the processes typically used to form alkylated aryl phosphates produce triphenyl phosphate (“TPP”) as a by-product of the alkylated phenyl phosphate formation reaction and is unwanted in the final product because of environmental concerns For example, TPP has been classified as a marine pollutant in some jurisdictions. Thus, it would be desirable to provide for alkylated aryl phosphates flame retardants suitable for use in polyurethane or polyisocyanurate foams having reduced amounts of TPP, when compared to currently available products, and also flame retarded polyurethane or polyisocyanurate foams also containing reduced amounts of TPP.